#!/usr/bin/python2.5

#

# Copyright 2008 the Melange authors.

#

# Licensed under the Apache License, Version 2.0 (the "License");

# you may not use this file except in compliance with the License.

# You may obtain a copy of the License at

#

#   http://www.apache.org/licenses/LICENSE-2.0

#

# Unless required by applicable law or agreed to in writing, software

# distributed under the License is distributed on an "AS IS" BASIS,

# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

# See the License for the specific language governing permissions and

# limitations under the License.

"""Helper functions for sending out notifications.

"""

__authors__ = [

  '"Lennard de Rijk" <ljvderijk@gmail.com>',

  ]

import time

from django.template import loader

from django.utils.encoding import force_unicode

from django.utils.translation import ugettext

# We cannot import soc.logic.models notification nor user here

# due to cyclic imports

from soc.logic import accounts

from soc.logic import dicts

from soc.logic import mail_dispatcher

from soc.logic import system

from soc.views.helper import redirects

DEF_NEW_NOTIFICATION_MSG = ugettext(

    "You have received a new Notification.")

DEF_INVITATION_MSG_FMT = ugettext(

    "Invitation to become a %(role_verbose)s for %(group)s.")

DEF_NEW_REQUEST_MSG_FMT = ugettext(

    "New Request Received from %(requester)s to become a %(role_verbose)s "

    "for %(group)s")

DEF_NEW_GROUP_MSG_FMT = ugettext(

    "Your %(application_type)s for %(group_name)s has been accepted.")

DEF_NEW_REVIEW_SUBJECT_FMT = ugettext(

    "New %s Review on %s")

DEF_WELCOME_MSG_FMT = ugettext("Welcome to %(site_name)s, %(name)s,")

DEF_GROUP_INVITE_NOTIFICATION_TEMPLATE = 'soc/notification/messages/' \

    'invitation.html'

DEF_NEW_REQUEST_NOTIFICATION_TEMPLATE = 'soc/notification/messages/' \

    'new_request.html'

DEF_NEW_REVIEW_NOTIFICATION_TEMPLATE = 'soc/notification/messages/' \

    'new_review.html'

DEF_NEW_GROUP_TEMPLATE = 'soc/group/messages/accepted.html'

def sendInviteNotification(entity):

  """Sends out an invite notification to the user the request is for.

  Args:

    entity : A request containing the information needed to create the message

  """

  from soc.logic.models.user import logic as user_logic

  from soc.views.models.role import ROLE_VIEWS

  invitation_url = "http://%(host)s%(index)s" % {

      'host' : system.getHostname(),

      'index': redirects.getInviteProcessRedirect(entity, None),

      }

  role_params = ROLE_VIEWS[entity.role].getParams()

  message_properties = {

      'role_verbose' : role_params['name'],

      'group': entity.group.name,

      'invitation_url': invitation_url,

      }

  subject = DEF_INVITATION_MSG_FMT % {

      'role_verbose' : role_params['name'],

      'group' : entity.group.name

      }

  template = DEF_GROUP_INVITE_NOTIFICATION_TEMPLATE

  from_user = user_logic.getForCurrentAccount()

  sendNotification(entity.user, from_user, message_properties, subject, template)

def sendNewRequestNotification(request_entity):

  """Sends out a notification to the persons who can process this Request.

  Args:

    request_entity: an instance of Request model

  """

  from soc.logic.helper import notifications

  from soc.logic.models.role import ROLE_LOGICS

  from soc.logic.models.user import logic as user_logic

  # get the users who should get the notification

  to_users = []

  # retrieve the Role Logics which we should query on

  role_logic = ROLE_LOGICS[request_entity.role]

  role_logics_to_notify = role_logic.getRoleLogicsToNotifyUponNewRequest()

  # the scope of the roles is the same as the scope of the Request entity

  fields = {'scope': request_entity.group,

            'status': 'active'}

  for role_logic in role_logics_to_notify:

    roles = role_logic.getForFields(fields)

    for role_entity in roles:

      # TODO: this might lead to double notifications

      to_users.append(role_entity.user)

  # get the user the request is from

  user_entity = request_entity.user

  message_properties = {

      'requester_name': user_entity.name,

      'entity': request_entity,

      'request_url': redirects.getProcessRequestRedirect(request_entity, None)}

  subject = DEF_NEW_REQUEST_MSG_FMT % {

      'requester': user_entity.name,

      'role_verbose' : request_entity.role,

      'group' : request_entity.group.name

      }

  template = DEF_NEW_REQUEST_NOTIFICATION_TEMPLATE

  for to_user in to_users:

    notifications.sendNotification(to_user, None, message_properties,

                                   subject, template)

def sendNewGroupNotification(entity, params):

  """Sends out an invite notification to the applicant of the group.

  Args:

    entity : An accepted group application

  """

  url = "http://%(host)s%(redirect)s" % {

      'redirect': redirects.getApplicantRedirect(entity,

      {'url_name': params['group_url_name']}),

      'host': system.getHostname(),

      }

  message_properties = {

      'application_type': params['name'],

      'group_type': params['group_name'],

      'group_name': entity.name,

      'url': url,

      }

  subject = DEF_NEW_GROUP_MSG_FMT % {

      'application_type': params['name'],

      'group_name': entity.name,

      }

  template = DEF_NEW_GROUP_TEMPLATE

  for to in [entity.applicant, entity.backup_admin]:

    if not to:

      continue

    sendNotification(to, None, message_properties, subject, template)

def sendNewReviewNotification(to_user, review, reviewed_name, redirect_url):

  """Sends out a notification to alert the user of a new Review.

  Args:

    to_user: The user who should receive a notification

    review: The review which triggers this notification

    reviewed_name: Name of the entity reviewed

    redirect_url: URL to which the follower should be sent for more information

  """

  message_properties = {'redirect_url': redirect_url,

      'reviewer_name': review.author_name(),

      'reviewed_name': reviewed_name,

      }

  # determine the subject

  review_type = 'public' if review.is_public else 'private'

  subject =  DEF_NEW_REVIEW_SUBJECT_FMT % (review_type, reviewed_name)

  template = DEF_NEW_REVIEW_NOTIFICATION_TEMPLATE

  # send the notification from the system

  sendNotification(to_user, None, message_properties, subject, template)

def sendNotification(to_user, from_user, message_properties, subject, template):

  """Sends out a notification to the specified user.

  Args:

    to_user : user to which the notification will be send

    from_user: user from who sends the notifications (None iff sent by site)

    message_properties : message properties

    subject : subject of notification email

    template : template used for generating notification

  """

  from soc.logic.models.notification import logic as notification_logic

  from soc.logic.models.site import logic as site_logic

  if from_user:

    sender_name = from_user.name

  else:

    site_entity = site_logic.getSingleton()

    sender_name = 'The %s Team' % (site_entity.site_name)

  new_message_properties = {

      'sender_name': sender_name,

      'to_name': to_user.name,

      }

  message_properties = dicts.merge(message_properties, new_message_properties)

  message = loader.render_to_string(template, dictionary=message_properties)

  fields = {

      'from_user': from_user,

      'subject': subject,

      'message': message,

      'scope': to_user,

      'link_id': 't%i' % (int(time.time()*100)),

      'scope_path': to_user.link_id

  }

  key_name = notification_logic.getKeyNameFromFields(fields)

  # create and put a new notification in the datastore

  notification_logic.updateOrCreateFromKeyName(fields, key_name)

def sendNewNotificationMessage(notification_entity):

  """Sends an email to a user about a new notification.

    Args:

      notification_entity: Notification about which the message should be sent

  """

  from soc.logic.models.site import logic as site_logic

  from soc.views.models.notification import view as notification_view

  # create the url to show this notification

  notification_url = "http://%(host)s%(index)s" % {

      'host' : system.getHostname(),

      'index': redirects.getPublicRedirect(notification_entity,

          notification_view.getParams())}

  sender = mail_dispatcher.getDefaultMailSender()

  site_entity = site_logic.getSingleton()

  site_name = site_entity.site_name

  # get the default mail sender

  default_sender = mail_dispatcher.getDefaultMailSender()

  if not default_sender:

    # no valid sender found, abort

    return

  else:

    (sender_name, sender) = default_sender

  to = accounts.denormalizeAccount(notification_entity.scope.account).email()

  # create the message contents

  messageProperties = {

      'to_name': notification_entity.scope.name,

      'sender_name': sender_name,

      'to': to,

      'sender': sender,

      'site_name': site_name,

      'subject': force_unicode(DEF_NEW_NOTIFICATION_MSG),

      'notification' : notification_entity,

      'notification_url' : notification_url

      }

  # send out the message using the default new notification template

  mail_dispatcher.sendMailFromTemplate('soc/mail/new_notification.html',

                                       messageProperties)

def sendWelcomeMessage(user_entity):

  """Sends out a welcome message to a user.

    Args:

      user_entity: User entity which the message should be send to

  """

  from soc.logic.models.site import logic as site_logic

  # get site name

  site_entity = site_logic.getSingleton()

  site_name = site_entity.site_name

  # get the default mail sender

  default_sender = mail_dispatcher.getDefaultMailSender()

  if not default_sender:

    # no valid sender found, should not happen but abort anyway

    return

  else:

    sender_name, sender = default_sender

  to = accounts.denormalizeAccount(user_entity.account).email()

  # create the message contents

  messageProperties = {

      'to_name': user_entity.name,

      'sender_name': sender_name,

      'to': to,

      'sender': sender,

      'subject': DEF_WELCOME_MSG_FMT % {

          'site_name': site_name,

          'name': user_entity.name

          },

      'site_name': site_name,

      'site_location': 'http://%s' % system.getHostname(),

      }

  # send out the message using the default welcome template

  mail_dispatcher.sendMailFromTemplate('soc/mail/welcome.html',

                                       messageProperties)